Rotary-finishing machine

ABSTRACT

In a rotary finishing machine of the type generally comprising a rotatable bowl adapted to contain a mass of abrasive finishing media, means for rotating the bowl, and spindle means for turning workpieces in the path of the mass of abrasive finishing media during rotation of the bowl, the spindle means is arranged for vertical, angular, and radial adjustments and is pivotally supported in a manner designed to facilitate insertion and removal of workpieces.

United States Patent Inventors Frank W. Porter [56] References CitedMontgomery; UNITED STATES PATENTS A I No Add, 2,664,676 1/1954 Cuppers51/7 1 2,749, 619 6 1 517 Filed p I969 669 l 5 S eeper paemed 17 197]Primary Examiner-William R. Armstrong Assign m Equipmem Altorney AllenJ. Hoover Addison, [1].

ABSTRACT: In a rotary finishing machine of the type ROTARY'FINISHINGMACHINE generally comprising a rotatable bowl adapted to contain a 26claims lo mass of abrasive finishing media, means for rotating the bowl,us. Cl 51/7, and p n l means for urning workpieces in the path of the51/19 mass of abrasive finishing media during rotation of the bowl, Int.Cl. B24!) 19/00 the spindle means is arranged for vertical, angular, andradial Field of Search 51/7, 19, adjustments and is pivotally supportedin a manner designed 164, 17, 6 to facilitate insertion and removal ofworkpieces.

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SHEET b 0F 5 ROTARY-FINISHING MACHINE BACKGROUND OF THE INVENTION Thisinvention pertains to rotary finishing machines for use in deburring,cleaning, polishing, and other finishing, of the type generallycomprising a rotatable bowl adapted to contain a mass of abrasivefinishing media, means for rotating the bowl, and spindle means forturning workpieces in the path of the mass of abrasive finishing media.

The bowl of a conventional machine of this type has a generallycylindrical wall and a generally circular bottom wall integral at itsouter periphery with the lower periphery of the generally cylindricalwall. in at least a lower portion of the generally cylindrical wall,perforations are provided for screening the mass of abrasive finishingmedia so as to permit radially outward discharge of abrasive fines andother waste materials and retain the remainder of the charge or mass ofabrasive finishing media within the bowl. Washing liquid, such as asolution of detergent in water, may be introduced into the bowl duringrotation of the bowl through a spray head or the like. Such washingliquid helps to remove abrasive fines and other waste materials and isdischarged through the perforations in the generally cylindrical wall ofthe bowl. Usually, the discharged matter is confined by an outerstationary protective housing and falls into a trough beneath from whichit is carried to a drain. Such a housing also serves to protect themachine operator from injury caused by rotation of the bowl or dischargeof matter from the bowl.

In a conventional machine of this type, the workpieces are held insuitable chucks or collets and are turned in the path of the mass ofabrasive finishing media by suitable arranged rotatable spindles.Usually, from one to three workpieces are finished at one time inregularly spaced relationship in a generally annular useful work zonewithin the bowl. The abrasive finishing media may range in size fromfine grits for use in polishing to heavy chips for use in heavydeburring and may be formed of any, of a variety of natural,manufactured, and composite materials.

Conventionally, each spindle has a spindle housing, which is suitablysupported within the bowl, and a spindle body, which is supported by andjoumaled within the spindle housing. Furthermore, each spindle formspart of spindle means additionally comprising a base or pedestal, aspindle arm supported by the base or pedestal above the bowl so as toextend generally radially inwardly with respect to the bowl, structureconnected to the spindle arm supporting the spindle housing in agenerally vertical position in the interior of the bowl, and a colletchuck adapted to releasably chuck workpieces to the lower end of thespindle body. Conventionally, a motor mounted to the spindle housing isused to rotate the spindle body within the spindle housing in such amanner as to turn workpieces held by the collet chuck in the path of theabrasive finishing media in the bowl.

It is desirable that the operator be able to adjust the position andorientation of the spindle in order to permit workpieces of varyingsizes and shapes to be finished in varying amounts of abrasive finishingmedia. In previous rotary finishing machines of the type to which thisinvention pertains, it has been necessary to use either a manuallyoperated jack screw or an overhead crane or the like to raise or lowerthe spindle, and other possible adjustments of the position andorientation are limited in applicability. Accordingly, there is a needfor improvements in such rotary finishing machines whereby vertical,angular, and radial adjustments of the position and orientation of thespindle may be made easily and with minimal effort.

SUMMARY OF THE INVENTION It is the principal object of this invention toprovide an imradial adjustments of the position and orientation of thespindle may be made easily and with minimal effort.

It is another object of this invention to provide such a rotaryfinishing machine in which a motor is used to raise or lower thespindle.

It is a further object of this invention to provide a rotary finishingmachine in which the same motor is used both to turn workpieces and toeffect adjustments of the height of the spindle.

Other objects of this invention are to permit the orientation of thespindle housing with respect to the longitudinal axis of the spindle armto be selectively adjusted and, furthermore, to

permit the spindle arm to be selectively adjustable in extension.

The preceding objects may be attained in a rotary finishing machine ofthe type generally comprising a rotatable bowl adapted to contain a massof abrasive finishing media, means for rotating the bowl, and spindlemeans for turning workpieces in the path of the mass of abrasivefinishing media, in which the spindle means comprises a base orpedestal, a spindle arm supported by the base in such a manner as tonormally extend generally radially inwardly with respect to the bowl, aspindle housing, a spindle body supported by and joumaled to the spindlehousing for turning movement within the spindle housing, support meanssupporting the spindle housing in such a manner as to permitlongitudinal movement of the spindle housing along the axis of thespindle body, and a motor supported by the spindle housing and adaptedto turn the spindle body within the spindle housing. Preferably, thespindle means further comprises a releasable clamp, which is adapted todraw together portions of the support means against the spindle housingon opposite sides of an axial slot in the support means, and a colletchuck, which is operatively associated with the spindle body and isadapted to releasably chuck workpieces adjacent the lower end of thespindle body. The foregoing features are conventional in the spindlemeans of rotary finishing machines of this type.

In accordance with the principles of this invention, the spindle meansfurther comprises means driven by the motor for selectively adjustingthe position of the spindle housing with respect to the support means.Preferably, such means comprises an Acme thread or other thread formedalong the spindle body in combination with a thread follower carried bythe support means and movable through an axial slot in the spindlehousing selectively into and out of engagement with the thread.Preferably, the motor which is used to turn the spindle body. within thespindle housing is a reversible electric motor adapted to turn thespindle body selectively in either direction. Thus, the spindle may beraised, by engagement of the thread follower with the thread andsubsequent operation of the motor in one direction, or lowered, byengagement of the thread follower with the thread and subsequentoperation of the motor in the opposite direction. The same motor may beused to turn workpieces in the path of the abrasive finishing media upondisengagement of the thread follower from the thread and subsequentoperation of the motor in either direction as desired.

It is a feature of a rotary finishing machine embodying the principlesof this invention that the spindle means is connected to the spindle armby structure comprising adjusting means for selectively adjusting theorientation of the spindle housing with respect to the longitudinal axisof the spindle arm. Preferably, the adjusting means comprises means forselectively adjusting the orientation of the spindle housing in a planewhich generally comprises the longitudinal axis of the spindle arm andmeans for selectively adjusting the orientation of the spindle housingin a plane which is substantially perpendicular to the longitudinal axisof the spindle arm.

It is another feature of such a rotary finishing machine that thespindle arm comprises outer and inner mutually telescoping members, oneof the mutually telescoping members being supported by the base, theother being connected to the support means, in combination with meansfor selectively adjusting the relative positions of the respectivemutually telescoping members.

It is yet another feature of such a rotary finishing machine that thespindle arm may be pivotally mounted to the base for pivotal movementbetween an operative position wherein the spindle arm is extendedradially inwardly with respect to the bowl and an inoperative positionwherein the spindle arm is pivoted upwardly from the operative position.Preferably, the spindle arm is pivotally mounted to the base for pivotalmovement about an axis of pivotal movement, preferably generallyhorizontal, which is oblique to a vertical plane comprising the axis ofthe spindle arm. In that instance, the spindle means preferablycomprises moving means, such as fluid-driven cylinder mechanism, forselectively moving the spindle arm between the operative position andthe inoperative position.

These and other objects, features, and advantages of this invention willbe evident from the following description, with the aid of the attacheddrawings, of a preferred embodiment of this invention.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a side elevational view of a rotary finishing machineembodying the principles of this invention, showing a spindle in araised position;

FIG. 2 is a top plan view of the rotary finishing machine of FIG. 1;

FIG. 3 is a partly broken away front elevational view of the rotaryfinishing machine of FIG. 1;

FIG. 4 is a sectional view, taken substantially along line 4-- 4 of FIG.3 in the direction of the arrows;

FIG. 5 is a sectional view, on an enlarged scale, taken substantiallyalong line $-5 of FIG. 4 in the direction of the arrows, showing thespindle in a lowered position;

FIG. 6 is a sectional view, taken substantially along line 6- 6 of FIG.5 in the direction of the arrows;

FIG. 7 is a sectional view, taken substantially along line 7 7 of F IG.3 in the direction of the arrows;

FIG. 8 is a sectional view, taken substantially along line 8- 8 of FIG.5 in the direction of the arrows;

FIG. 9 is a fragmentary front elevational view, also on an enlargedscale, of portions of the rotary finishing machine as shown in FIG. 3,showing the spindle in an intermediate positiongand FIG. 10 is asectional view taken substantially along line 10-10 of FIG. 8 in thedirection ofthe arrows.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the drawings, there is showna rotary finishing machine 10 for use in deburring, cleaning, polishing,and other finishing. The rotary finishing machine 10, which constitutesa preferred embodiment of this invention, generally comprises arotatable bowl 12 adapted to contain a mass of abrasive finishing media(not shown), means 14 for rotating the bowl, and spindle means 16 forturning workpieces in the path of the mass of abrasive finishing mediaduring rotation of the bowl 12. A single spindle means 16 is shown infull throughout the drawings. In FIGS. 2 and 3, a second spindle means16', similar to the spindle means 16, is shown diagrammatically forpurposes to be explained hereinafter. Additional spindle means (notshown), similar to the spindle means 16 and 16', may be provided ifdesired. The plural spindle means 16, 16, etc. should be arranged in aregularly spaced relationship around the periphery of the bowl 12. Thus,a corresponding number of workpieces may be finished, at one time, in aregularly spaced relationship in a generally annular useful work zonewithin the bowl 12.

Means (not shown) may be provided for introducing washing liquid, suchas a solution of detergent in water, into the bowl 12 during rotation ofthe bowl 12. Preferably, such means are in the form of conventionalspray heads arranged to spray washing liquid onto the workpieces.

The bowl 12 comprises a generally cylindrical wall 18 and a generallycircular bottom wall 20 integral with the wall 18. Preferably the wall18 is provided with a plurality of removable screen panels (not shown)of the type disclosed in the copending application of Achille K.Ferrara, Ser. No. 800,387 filed Feb. 19, 1969 and assigned to theassignee of the present invention. Alternatively, a lower portion of thewall portion of the wall 18 itself may be provided with a multiplicityof uniform enlarged perforations, and screen cloth or the like ofsuitable mesh size may be wrapped around the perforated portion of thewall 18 and suitably fastened in place. The perforated screen panels, ifused, or the perforated portion of the wall 18, if used, serves toscreen the mass of abrasive finishing media so as to permit radiallyoutward discharge of abrasive fines and retain the remainder of the massof abrasive finishing media. Other waste materials and washing liquidare discharged with the abrasive fines.

The means 14 for rotating the bowl 12 is conventional and comprises anelectric motor (not shown) and a right-angle speed reducer (not shown)preferably interconnected by means of a split-sheave variable-speedpulley system, indicated generally at 26, employing a V-belt 28.

The rotary finishing machine 10 further comprises an outer stationaryprotective housing 36 which serves to confine matter discharged from thebowl 12 during operation of the machine 10. The housing '36 also servesto protect the machine operator from injury caused by rotation of thebowl 12 or by discharge of matter from the bowl 12. The housing 36defines a trough (not shown) to which matter discharged from the bowl 12falls. The trough carries such matter to a drain (not shown). Thehousing 36 may be designed in multiple interfastened sections (notshown) so as to be capable of being disassembled to give access to thebowl 12. l

Further details of the bowl 12, the means 14 for rotating the bowl 12,and the housing 36, as described in the preceding paragraphs, are beyondthe scope of the present disclosure and may be supplied readily by thoseskilled in the art. Next to be described is the spindle means 16, whichis constructed in accordance with the principles of this invention. Itshould be understood, that the spindle means 16' and any additionalspindle means (not shown) are similarly constructed. As mentioned, theplural spindle means 16, 16, etc. should be arranged in a regularlyspaced relationship around the periphery of the bowl 12.

As shown, the spindle means 16 comprises a spindle 40 and spindlesupporting structure, indicated generally at 42. The spindle 40 isdesigned to turn workpieces in the path of the mass of abrasivefinishing media contained in the bowl 12. The supporting structure 42 isdesigned to permit and facilitate vertical, angular, and rotaryadjustments of the position of the spindle 40 with respect to thelateral and bottom walls of the bowl 12.

The spindle 40 generally comprises a spindle housing 44 and a spindlebody 46 supported within and journaled to the spindle housing 44 forturning movement .within the spindle housing 44. The spindle supportingstructure 42 generally comprises a generally cylindrical base orpedestal 48, aspindle arm 50 supported by the base or pedestal 48 abovethe bowl 12 in such a manner as to normally extend generally radiallyinwardly with respect to the bowl l2, and support means 52 connected tothe spindle arm 50 for supporting the spindle housing 44 in such amanner as to permit longitudinal movement of the spindle housing 44along the axis of the spindle body 46. A motor 54, which is supported bythe spindle housing 44, is adapted to turn the spindle body 46 withinthe spindle housing 44.

The spindle housing 44 comprises an elongated generally tubular member60, which has a radially outwardly extending upper flange 62 and anelongated axial slot 66, lower bearing retaining structure 70, which isbolted or otherwise integrally attached to the flange 62, an outer wallmember 72, which is bolted to the lower bearing supporting structure 70by means of a plurality of bolts 74, upper bearing supporting structure76, which is fastened to the outer wall member 72 by means of aplurality of bolts 78 (one shown), and bellows supporting structure 80,which is bolted or otherwise integrally attached to the upper bearingsupporting structure 76. The spindle body 46 is in the form of anelongated generally tubular member 90, which is rotatably fitted withinthe spindle generally tubular member and extends downwardly therefrom. Apulley 92 is mounted to the upper end portion 94 of the member forconjoint rotation with the member 90. A worm gear 96 is mounted to themember 90, immediately beneath the pulley 92, for conjoint rotation withthe member 90. The worm gear 96 has a lower hub portion 98 and an upperhub portion 100. The generally tubular member 90 of the spindle body 46is rotatably fitted within and extends downwardly from the generallytubular member 60 of the spindle housing 44. The spindle body 46 isjoumaled to the spindle housing 44 by means of an upper rolling-contactthrust bearing 102 intermediate the lower hub portion 98 of the wormgear 96 and the upper bearing retaining structure 76 and a lowerrolling-contact thrust bearing 104 intermediate the lower hub portion ofthe worm gear 96 and the lower bearing retaining structure 70.

A worm-supporting shaft is joumaled to opposite sides (not numberedlofthe outer wall member 72 of the spindle housing 44. A worm 112 ismounted to the shaft 110, in driving engagement with the worm gear 96,for conjoint rotation with the shaft 110. One end 114 (FIGS. 2 and 4) ofthe shaft 110 extends outwardly from the outer wall member 72 of thespindle housing 44, and a pulley 116 is mounted thereto for conjointrotation with the shaft 110. The motor 54 is in the fonn of anintermittently operable reversible electric motor and is strapped orotherwise suitably mounted to a reinforced mounting bracket 118, whichis welded or otherwise integrally attached to the outer wall member 72of the spindle housing 44. The output shaft 120 (FIGS. 2 and 4) of themotor extends in spaced parallel relation to the worm supporting shaft110. A pulley 122 is mounted to the output shaft 120 for conjointrotation. An endless belt 124 is used to drive the pulley 116 from thepulley 122 in such a manner as to turn the spindle body 46 within thespindle housing 44. A conventional tachometer 126 having an input pulley128 is mounted to the spindle housing 44 by means of a suitable bracket130. An endless belt 132 is used to drive the pulley 128 of thetachometer 126 from the pulley 92 on the spindle body 46.

As shown, the support means 52 is in the form of a generally squarecolumnar member 134 having a generally cylindrical opening 136 slidablyreceiving the spindle housing 44. Furthermore, as shown in FIGS. '8 and9, the spindle housing 44 is slidably keyed to the support means bymeans of a key 138, which is seated in a suitable pocket 1380 in themember 134 and is slidable in a suitable elongated groove 138b in themember 90.

In accordance with the principles of this invention, the spindle means16 further comprises means 140 driven by the motor 54 for selectivelyadjusting the position of the spindle housing 44 with respect to thesupport means 52 along the axis of the spindle body 46. Moreparticularly, the means 140 comprises a thread 142 which is formed alongthe spindle body 46, in combination with a thread follower 144, which iscarried by the support means 52 and is movable through the axial slot 68in the spindle housing 44 into and out of engagement with the thread142. As shown, the thread 142 is an Acme thread, although other threadforms also would be suitable. The thread follower 144 comprises ahalf-nut 146 and a drawbolt 148. The half-nut 146 is slidably fitted ina suitably shaped slot 150 formed in the wall 152 of the support means52. A plate 154 having a threaded opening 156 is welded or otherwisesuitably attached to the wall 152 of the support means 52 at the marginof the slot 150. The drawbolt 148 has a threaded shank 158, which isthreadably engaged with the threaded opening 156 in the plate 154, andan enlarged circular head 160, which is rotatably fitted in a circularsocket 162 formed in the half-nut 146 and is held in place by means of aplate 164 having an unthreaded circular opening 166 for the shank 158.The plate 164 is rigidly fastened 'to the half-nut 146, preferably bymeans of machine screws (not shown). A hand wheel 168 is mounted to theshank 158 of the drawbolt 148, outwardly of the plate 154, for conjointrotation with the drawbolt 148.

It is evident from the manner in which the aforenoted means 140 isconstructed, that, upon engagement of the thread follower 144 with thethread 142, the spindle body 46 acts as a jackscrew with the result thatrotation of the spindle body 46 within the spindle housing 44 by themotor 54, in the manner described hereinbefore, either raises or' lowersthe spindle housing 44 with respect to the support means 52 along theaxis of the spindle body 46, depending on the direction of rotation ofthe spindle body 46 within the spindle housing 44. Because the motor 54is in the form of a selectively reversible electric motor, as mentionedherebefore, the position of the spindle housing 44 with respect to thesupport means 52 may be selectively adjusted upwardly or downwardly, asdesired.

The spindle means 16 further comprises means (not numbered) forreleasably holding the spindle housing 44 in a selected position withrespect to the support means 52. As shown, such means comprises aconventional releasable clamp 182 adapted to draw together portions ofthe support means 52 against the spindle housing 44 on opposite sides ofan axial slot 184 in the support means 52. As shown, the clamp 182 is inthe form of a flanged member 186 fastened to the support means 52 at oneside of the slot 184 by means of machine screws 188 (FIGS. 9 and 10) anda flanged member 190 fastened to the support means 52 at the oppositeside of the slot 184 by means of machine screws 192 (FIG. 10). Theflanged members 186 and 190 are formed with aligned openings, 194 and196 respectively. A bolt 198 passes through the aligned openings 194 and196 and serves, when tightened, to draw together the portions of thesupport means 52 to which the respective flanged members 186 186 and 190are fastened. When the bolt 198 is loosened, the position of the spindlehousing 44 with respect to the support means 52 may be adjusted in themanner described hereinabove.

The spindle means 16 further comprises a conventional collet chuck 200operatively associated with the spindle body 46 and adapted toreleasably chuck workpieces to the spindle body 46 adjacent the lowerend 202 of the spindle body. The collet chuck 200 comprises an adjustingsleeve 204, which is integrally connected to the lower end 202 of thespindle body 46 within an enlarged elongated axial socket 206 in thespindle body 46, and a gripping member 208, which is movable axiallywith respect to the spindle body 46 within the adjusting sleeve 204. Asshown, the adjusting sleeve 204 has a radially outwardly extendingflange 210 and an outwardly opening conical camming surface 212 and isintegrally connected to the lower end 202 of the spindle body 46 bymeans of an internally threaded collar 214 threadably engaging asuitably threaded end portion 216 of the spindle body 46. The collar 214has a radially inwardly extending flange 218 adapted to hold the flange210 of the adjusting sleeve 204 against the end surface 220 of thespindle body 46. The gripping member 208, which is generally tubular, asshown, has an externally threaded end portion 220 and is axially slottedin such a manner as to form a plurality of axially extending fingerportions 222, as is known. The gripping member 208 should be made ofspring steel or other inherently resilient material, as is known. Therespective finger portions 222 of the gripping I member 208 have outerconical camming surfaces 224 corresponding to the camming surface 212 ofthe adjusting sleeve 204. The threaded end. portion of the grippingmember 208 is threadably connected to a suitably threaded axial socket226 in a guiding member 228, which is slidably fitted within the axialsocket 206 in'the spindle body 46 above the adjusting sleeve 204. Theguiding member 228 is permitted a limited amount of axial movementwithin the axial socket 206 in the spindle body 46. Thus, the grippingmember 208 is movable axially with respect to the spindle body 46between a retracted position and an extended position, as mentionedhereinbefore. As the gripping member 208 is moved from the extendedposition toward the retracted position, the camming surfaces 208 of therespective finger portions 222 of the gripping member 208 are drawnagainst the camming surface 212 of the adjusting sleeve 204 in such amanner as to bend the finger portions 222 radially inwardly. Thus, inthe retracted position of the gripping member 208, the finger portions222 are radially contracted, and, in the extended position of thegripping member 208, the finger portions 222 are radially expanded.

The collet chuck 200 further comprises a push rod 230, which extendsthrough an axial bore 232 in the spindle body 46 and is connected to thegripping member 208, biasing means 234 acting on the push rod 230 tobias the gripping member 208 to the retracted position, and actuatingmeans 236 arranged to act on the push rod 230 in opposition to thebiasing means 234 to move the gripping member 208 to the extendedposition. The push rod 230 is guided within upper and lower sleevebearings, 238 and 240 respectively, which preferably are formed in onepiece with the spindle body 46, and is connected to the gripping member208 by means of a capscrew 242, which passes through an axial opening244 in the guide member 228 and threadably engages a suitably threadedaxial socket 246 in the lower end 248 of the push rod 230. An elongatedstud 250 threadably engages a suitably threaded axial socket 246 in theupper end 252 of the push rod 230 and serves as an axial extension ofthe push rod 230. The stud 250 is held in place by means of a nut 254and extends upwardly through an opening 256 in the aforementionedbellows supporting structure 80. A plate 258 having an upwardly turnedlateral flange 260 and an opening 262 for the stud 250 is fastened tothe bellows supporting structure 80 by means of capscrews 264. The stud250 passes freely upwardly through the opening 262 in the plate 260. Acover member 270, which has a circular top wall 272 and a downwardlyextending cylindrical wall 274, is welded or otherwise rigidly attachedto the upper end 276 of the stud 250. The biasing means 234 is in theform of a helical spring 278 between the plate 260 and the top wall 272of the cover member 270. The plate 260 forms part of bellows housingstructure 284, which further comprises a cover member 286 having a topwall 288 provided with a nipple 290 and having a downwardly extendinggenerally cylindrical wall 292 welded or otherwise rigidly attached tothe flange 262 of the plate 260. A flexible bellows 294 is suitablyfastened within the cover member 286 of the bellows housing structure284 and is disposed in generally contiguous relation to the cover member270 on the stud 250. The bellows 294 may be pressurized ordepressurized, through the nipple 290, by conventional pneumatic means(not shown). When the bellows 294 is pressurized, the push rod 230 isdriven downwardly against the biasimposed by the spring 278 and thecollet member 208 is moved to the extended position. When the bellows294 is depressurized, the collet member 208 is restored to the retractedposition by the spring 278. Also, when the bellows 294 is depressurized,there is sufficient clearance between the bellows 294 and the covermember 270 on the stud 250 for the cover member 270 to'turn freely withrespect to the bellows 294. As is evident, the cover member 270 turnsconjointly with the spindle body 46.

Herein a longitudinal axis taken through the radial center of the arm 50is considered to be the "longitudinal axis" of the spindle arm 50. lnaccordance with the principles of this invention, the spindle means 16further comprises adjusting means (not numbered) for selectivelyadjusting the orientation of the spindle body 46 with respect to thelongitudinal axis of the spindle arm 50. The orientation of the spindlebody 46 is defined by the orientation of the longitudinal axis of thespindle body 46. More particularly, the adjusting means comprises means302 for selectively adjusting the orientation of the spindle body 46 ina plane which generally comprises the longitudinal axis of the spindlearm 50 and means 304for selectively adjusting the orientation of thespindle body 46 in a plane which is substantially perpendicular to thelongitudinal axis of the spindle arm 50.

The means 302 for selectively adjusting the orientation of the spindlebody 46 in a plane which generally comprises the longitudinal axis ofthe spindle am 50 comprises a bracket 310 having an outer wall 312 andopposite sidewalls 314 and 316. An outwardly directed stub shaft 318extends outwardly through an opening 320 in the outer wall 312 and iswelded or otherwise suitably integrally attached to the outer wall 312at an inner flange or boss 322. An inwardly directed stub shaft 324,which is slightly smaller in diameter than the stub shaft 318, extendsinwardly through an opening 326 in the sidewall 314 and is welded orotherwise integrally attached to the sidewall 314 at an outer flange orboss 328. A similar stub shaft 330, which is axially aligned with thestub shaft 324, extends inwardly through an opening 332 in the sidewall316 and is welded or otherwise integrally attached to the sidewall 316at an outer flange or boss 334.

The stub shaft 318 is aligned with the spindle arm 50 and is connectedthereto in a manner to be described hereinafter. The stub shaft 324passes through an annular spacer 336 between the wall 314 of the bracket310 and the support means 52. The stub shafts 324 and 326 are rotatablyfitted into aligned openings, 338 and 340 respectively, on oppositesides of the support means 52 and pivotally support the support means 52in such a manner as to permit pivotal movement of the support means 52upon the axis of pivotal movement defined by the stub shafts 324 and326. Such movement of the support means 52 produces changes in theorientation of the spindle body 46 in a plane which generally comprisesthe longitudinal axis of the spindle arm 50, that is, in a plane whicheither is in closely spaced substantially parallel relation to thelongitudinal axis of the spindle arm 50 or, as shown, actually comprisesthe longitudinal axis of the spindle arm 50.

The sidewall 314 of the bracket 310 has spaced downwardly extending legs352. The aforenoted means 302 further comprises a shaft 354 (FIG. 10),which is journaled in openings 356 (one shown) in protruding generallyannular lug portions 358 (one shown) in protruding generally annular lugportions 358 (one shown) of the respective legs 353, a hand wheel 360,which is suitably fastened to the shaft 354, a worm 362, which ismounted on the shaft 354 for conjoint rotation, and a partial worm gear364, which engages the worm 362 and is rigidly mounted to the supportmeans 52 by means of a plurality of capscrews 366. As shown, a crankhandle 368 is operatively mounted to the hand wheel 360. Rotation of thehand wheel 360 produces pivotal movement of the support means 52 uponthe axis of pivotal movement defined by the stub shafts 324 and 326 andthus produces the desired component of adjustment of the orientation ofthe spindlebody 46 with respect to the longitudinal axis of the spindlearm 50.

The stub shaft 318 is rotatably fitted within an elongated generallytubular member 380, which forms part of the spindle arm 50 and is keyedto the generally tubular member 380 for rotation therewith by means of aplurality of studs 382 having threaded heads 384 and radially inwardlyextending shanks 386. The heads 384 of the respective studs 382 fit intoan annular groove 390 formed in the stub shaft 318, which thereby ispermitted to rotate within the generally tubular member 380 yet isprevented from moving axially with respect to the generally tubularmember 380. Consequently, the bracket 310 is permitted pivotal movementabout the longitudinal axis of the stub shaft 318 and thus about thelongitudinal axis of the spindle arm 50. Such movement of the bracket310 produces changes in the orientation of the spindle body 46substantially in rotation about the longitudinal axis of the spindle arm50.

The means 304 for selectively adjusting the orientation of the spindlebody 46 in a plane which is substantially perpendicular'to thelongitudinal axis of the spindle arm 50 comprises a generally annularbracket 390, which has spaced downwardly extending legs 392 and iswelded or otherwise integrally attached to the generally tubular member380 ,in spaced relation to the outer wall 312 of the bracket 310, ashaft 394, which is journaled in openings 396 (one shown) in protrudinggenerally annular lug portions 398 of the respective legs 392, a handwheel 400, which is suitably fastened to the shaft 394, a worm 402,which is mounted on the shaft 394 for conjoint rotation, and a partialworm gear 404, which engages the worrn 402 and is rigidly mounted to theouter wall 312 of the bracket 310 by means of a plurality of capscrews406. As shown, a crank handle 408 is operatively mounted to the handwheel 400. Rotation of the hand wheel 400 produces pivotal movement ofthe bracket 310 about the longitudinal axis of the spindle arm 50 andthus produces the desired component of adjustment of the orientation ofthe spindle body 46 with respect to the longitudinal axis of the spindlearm 50;

Because adjustment of the orientation of the spindle body 46 withrespect to the longitudinal axis of the spindle arm 50 does not requirelifting of any heavy components, the hand wheel 360 and the hand wheel400 operate satisfactorily. However, for'added convenience, either theworm 362 otherwise driven by the hand wheel 360 or the worm 402otherwise driven by the hand wheel 400, or both conjointly orseparately, may be arranged to be driven in either direction by means ofan intermittently operable reversible electric motor (not shown) or thelike, details of which may be supplied readily by those skilled in theart.

The spindle arm 50 comprises outer and inner mutually telescopingmembers, a sleeve member 420 and the aforenoted elongated generallytubular member 380 respectively, and means 422 for adjusting theposition of the generally tubular member 380 with respect to the sleevemember 420. The generally tubular member 380 has an axial slot 424therein and extends through the sleeve member 420, which issubstantially shorter than the generally tubular member 380, fortelescoping movement within the sleeve member 380. The aforenoted means422 comprises an elongated externally threaded screw member 426, whichis journaled within the generally tubular member 380 in parallelrelation to the axial slot 424, a screw follower 432, which is slidablewithin the generally tubular member 380 and is threadably engaged withthe screw member 426, and means 434 which is supported by the sleevemember 420 and is extended through the axial slot 424 in slidingrelation to the generally tubular member 380 for holding the screwfollower 432 in fixed relation to the sleeve member 420 upon rotation ofthe screw member 426 with respect to the generally tubular member 380.The screw member 426 has an unthreaded shank portion 436. A thrustbearing 438 is threadably connected to a suitably threaded end portion440 of the generally tubular member 380. The shank portion 436 ofthescrew member 426 is journaled in the thrust bearing 438. A hand wheel442 is suitably fastened to the shank portion 436 of the screw member426, and, as shown, a crank handle 444 is operatively mounted to thehand wheel 442. Preferably, the screw member 426 is formed with a ballthread 446, as shown, and the screw follower 432 is in the form of aball nut 448 having a corresponding thread (not shown). Preferably, theaforenoted means 434 is in the form of a stud 450 having a threaded head452, which is threadably connected to the sleeve member 420 in asuitably threaded opening 454, and having a shank 456, which is extendedradially inwardly through the axial slot 424 and is seated in a suitablyformed socket 458 in the ball nut 448. The stud 450 prevents bothrotation and axial movement of the ball nut 448 with respect to thesleeve member 420.

The shank 456 of the stud 450 cooperates with the margins of the axialslot 424 in such a manner as to permit axial movement of the generallytubular member 380 with respect to the sleeve member 420 yet preventrotation of the generally tubular member 380 with respect to the sleevemember 420. Rotation of the hand wheel 442 produces adjustment of theaxial position of the generally tubular member 380 with respect to thesleeve member 420.

Because adjustment of the axial position of the generally tubular member380 with respect to the sleeve member 420 does not require lifting ofany heavy components, the hand wheel 442 operates satisfactorily.However, for added convenience, the screw member 426 may be arranged tobe selectively driven in either direction by means of an intermittentlyoperable reversible electric motor (not shown) or the like, details ofwhich may be supplied readily by those skilled in the art.

The spindle arm 50 is pivotally mounted to the base or pedestal 48 forpivotal movement between an operative position and an inoperativeposition. In the operative position, the spindle arm 50 is extendedradially inwardly with respect to the bowl 12. In the inoperativeposition, the spindle arm 50 is elevated from the operative position.

More particularly, spindle arm 50 is pivotally mounted to the base orpedestal 48 for pivotal movement about an axis of pivotal movementoblique to a vertical plane which comprises the longitudinal axis of thespindle arm 50. Preferably, the axis of pivotal movement of the spindlearm 50 with respect to the base or pedestal 48 is horizontal and isorientated at an angle of approximately 45 with respect to a verticalplane which comprises the longitudinal axis of the'spindle arm 50.Consequently, pivotal movement of the spindle arm 50 from the operativeposition draws a workpiece which is held by the aforenoted collet chuck200 upwardly and outwardly from the bowl 12. This is illustrated in FIG.3, wherein movement of the spindle means 16' from its operative positionto its inoperative position is illustrated diagrammatically. Also seeFIG. 2, in which the spindle means 16 is shown diagrammatically in itsinoperative position.

The sleeve member 420 of the spindle arm 50 is pivotally supported onthe base or pedestal 48 by means of opposite stub shafts, 460 and 462respectively, which are welded or otherwise integrally mounted to thesleeve member 420 in such a manner as to define an axis of pivotalmovement of the spindle arm 50 which is oriented as desired. The stubshaft 460 is suitably journaled to an upright arm 468 which is welded orotherwise rigidly attached to the base or pedestal 48. The stub shaft462 is similarly journaled to an upright arm 470, which is welded orotherwise rigidly attached to the base or pedestal 48 in diametricallyopposite relation to the arm 468. As shown in FIG. 3, the base orpedestal 48 is formed with an integral rest 472, which is adapted tosupport the sleeve member 420 and thus the spindle arm 50 when thespindle arm 50 is in the operative position, and is cut away, asindicated at 474, in order to permit the spindle arm 50 to be pivotedfrom the operative position to the inoperative position. Owing to thedistribution of weight inherent in the structure of the spindle means16, the spindle arm 50 is stable in the operative position.

The spindle means 16 further comprises moving means 480 for selectivelymoving the spindle arm 50 between the operative position and theinoperative position. As shown, the moving means 480 comprisesfluid-driven cylinder mechanism 482 intermediate the spindle arm 50 andthe base or pedestal 48. The mechanism 482 may be either pneumatic orhydraulic, the former being preferred, and, as shown, comprises acylinder case 484, which is pivotally connected to the base or pedestal48, and an extensible retractable rod 486, which is pivotally connectedto the spindle arm 50. A bracket 488 is welded or otherwise rigidlyconnected to the base or pedestal 48. A clevis 490 is suitablyintegrally attached to the lower end 492 of the cylinder case 484 and ispivotally connected to the bracket 488 at a pinned connection 494. Acrank arm 496 is welded or otherwise rigidly connected to the sleevemember 420 in such a manner as to extend upwardly and outwardly ingenerally perpendicular relation to the axis of pivotal movement of thespindlearm 50. A clevis 498 is suitably integrally attached to the upperend 500 of the rod 486 and is pivotally connected to the crank arm 496at a pinned connection 502. Details of suitable conduits and controlsfor the mechanism 482 are beyond the scope of the present disclosure andmay be supplied readily by those skilled in the art. The mechanism 482is arranged for selective application of fluid pressure in known mannerto pivotally move the spindle arm 50 from the operative position to theinoperative position and to hold the spindle arm 50 in the inoperativeposition until release of fluid pressure. Inherent damping in themechanism 482 permits the spindle arm 50 to drop slowly to the operativeposition upon release of fluid pressure.

Modifications and improvements within the scope of this invention may besuggested by this disclosure to those skilled in the art. Accordingly,the scope of this invention should be determined from the followingclaims.

We claim:

1. A rotary finishing machine comprising a rotatable bowl adapted tocontain a mass of abrasive finishing media, means for rotating saidbowl, and spindle means for turning workpieces in the path of said massof abrasive finishing media during rotation of said how], said spindlemeans comprising a base, a spindle arm supported by said base above saidbowl in such a manner as to normally extend generally radially inwardlywith respect to said bowl, a spindle housing, a spindle body supportedwithin and journaled to said spindle housing for turning movement withinsaid spindle housing, support means connected to said spindle arm forsupporting said spindle housing in such a manner as to permit movementof said spindle housing with respect to said support means along theaxis of said spindle body, a motor supported by said spindle housing andadapted to turn said spindle body within said spindle housing, and meansdriven by said motor for selectively adjusting the position of saidspindle housing with respect to said support means along the axis ofsaid spindle body.

2. The rotary finishing means of claim 1 wherein said means forselectively adjusting the position of said spindle housing axially withrespect to said support means along the axis of said spindle bodycomprises a thread, which is formed along said spindlebody, and a threadfollower, which is carried by said support means and is movable throughan axial slot in said spindle housing selectively into and out ofengagement with said thread.

3. The rotary finishing machine of claim 2 wherein said thread is anAcme thread.

4. The rotary finishing machine of claim 2 wherein said thread followercomprises a half-nut, which is slidably fitted in a slot formed in saidsupport means, and a drawbolt, which is adapted to draw said half-nutwithin said slot selectively into and out of engagement with saidthread.

5. The rotary finishing machine of claim 2 wherein said motor is in theform of a selectively reversible electric motor supported by saidspindle housing for movement therewith.

6. The rotary finishing machine of claim 2 wherein said spindle meansfurther comprises means for releasably holding said spindle housing in aselected position with respect to said support means.

7. The rotary finishing machine of claim 6 wherein said means forreleasably holding said spindle housing in a selected position withrespect to said support means comprises a releasable clamp adapted todraw together portions of said support means against said spindlehousing on opposite sides of an axial slot in said support means.

8. The rotary finishing machine of claim 1 wherein said spindlemeansfurther comprises a collet chuck operatively associated with saidspindle body and adapted to releasably chuck workpieces to said spindlebody adjacent the lower end of said spindle body.

9. The rotary finishing machine of claim 1 wherein said spindle arm hasa longitudinal axis and said support means is connected to said spindlearm by structure comprising adjusting means for selectively adjustingthe orientation of said spindle body with respect to the longitudinalaxis of said spindle arm.

10. The rotary finishing machine of claim 9 wherein said adjusting meanscomprises means for selectively adjusting the orientation of saidspindle body in a plane which generally comprises the longitudinal axisof said spindle arm.

11. The rotary finishing machine of claim 9 wherein said adjusting meanscomprises means for selectively adjusting the orientation of saidspindle body in a plane which is substantially perpendicular to thelongitudinal axis of said spindle arm.

12. The rotary finishing machine of claim 9 wherein said ad justingmeans comprises means for selectively adjusting the orientation of saidspindle housing in a plane which generally comprises the longitudinalaxis of said spindle arm and means for selectively adjusting theorientation of said spindle housing in a plane which is substantiallyperpendicular to the longitudinal axis of said spindle arm.

13. The rotary finishing machine of claim 1 wherein said spindle armcomprises outer and inner mutually telescoping members, one of saidmutually telescoping members being supported by said base, the other ofsaid mutually telescoping members being connected to said support means.

14. The rotary finishing machine of claim 13 further comprising meansfor selectively adjusting the axial position of said other of saidmutually telescoping members with respect to said one of said mutuallytelescoping members.

15. The rotary finishing machine of claim 14 wherein said inner mutuallytelescoping member is elongated and generally tubular and has an axialslot formed therein, and wherein said means for selectively adjustingthe axial position of said other of said mutually telescoping memberswith respect to said one of said mutually telescoping members comprisesan elongated externally threaded screw member joumaled within saidgenerally tubular member in parallel relation to said axial slot, ascrew follower slidable within said inner mutually telescoping memberand threadably engaged with said screw member, and means supported bysaid outer mutually telescoping member and extended through said axialslot is sliding relation to said inner mutually telescoping member forholding said screw follower in fixed relation to said outer mutuallytelescoping member upon rotation of said screw member with respect tosaid inner mutually telescoping member.

16. The rotary finishing machine of claim 13 wherein said outer mutuallytelescoping member is supported by said base and said inner mutuallytelescoping member is connected to said support means.

17. The rotary finishing machine of claim 16 further comprising meansfor selectively adjusting the axial position of said inner mutuallytelescoping member with respect to said outer mutually telescopingmember.

18. The rotary finishing machine of claim 17 wherein said inner mutuallytelescoping member is elongated and generally tubular and has an axialslot formed therein, and wherein said means for selectively adjustingthe axial position of said inner mutually telescoping member withrespect to said outer mutually telescoping member comprises an elongatedexternally threaded screw member joumaled within said inner mutuallytelescoping member in parallel relation to said axial slot, a screwfollower slidable within said inner mutually telescoping member andthreadably engaged with said screw member, and means supported by saidouter mutually telescoping section and extended through said axial slotin sliding relation to said inner mutually telescoping member forholding said screw follower in fixed relation to said outer mutuallytelescoping member upon rotation of said screw member with respect tosaid inner mutually telescoping member.

19. The rotary finishing machine of claim 1 in which said spindle arm ispivotally mounted to said base for pivotal movement between an operativeposition wherein said spindle arm is extended radially inwardly withrespect to said bowl and an inoperative position wherein said spindlearm is pivoted upwardly from said operative position. i

20. The rotary finishing machine of claim 19 wherein said spindle armhas an axis and is pivotally mounted to said base for pivotal movementabout an axis of pivotal movement oblique to a vertical plane whichcomprises the axis of said spindle arm. 5

21. The rotary finishing machine of claim 20 wherein the axis of pivotalmovement of said spindle arm is generally horizontal.

22. The rotary finishing machine of claim 19 wherein said base providesan integral rest for said spindle arm in said operative position andsaid spindle arm is stable in said operative position.

23. The rotary finishing machine of claim 19 wherein said spindle meansfurther comprises moving means for selectively moving said spindle armbetween said operative position and said inoperative position.

24. The rotary finishing machine of claim 23 wherein said moving meanscomprises fluid-driven cylinder mechanism arranged to move said spindleann from said operative position.

25. The rotary finishing machine of claim 24 wherein said

1. A rotary finishing machine comprising a rotatable bowl adapted tocontain a mass of abrasive finishing media, means for rotating saidbowl, and spindle means for turning workpieces in the path of said massof abrasive finishing media during rotation of said bowl, said spindlemeans comprising a base, a spindle arm supported by said base above saidbowl in such a manner as to normally extend generally radially inwardlywith resPect to said bowl, a spindle housing, a spindle body supportedwithin and journaled to said spindle housing for turning movement withinsaid spindle housing, support means connected to said spindle arm forsupporting said spindle housing in such a manner as to permit movementof said spindle housing with respect to said support means along theaxis of said spindle body, a motor supported by said spindle housing andadapted to turn said spindle body within said spindle housing, and meansdriven by said motor for selectively adjusting the position of saidspindle housing with respect to said support means along the axis ofsaid spindle body.
 2. The rotary finishing means of claim 1 wherein saidmeans for selectively adjusting the position of said spindle housingaxially with respect to said support means along the axis of saidspindle body comprises a thread, which is formed along said spindlebody, and a thread follower, which is carried by said support means andis movable through an axial slot in said spindle housing selectivelyinto and out of engagement with said thread.
 3. The rotary finishingmachine of claim 2 wherein said thread is an Acme thread.
 4. The rotaryfinishing machine of claim 2 wherein said thread follower comprises ahalf-nut, which is slidably fitted in a slot formed in said supportmeans, and a drawbolt, which is adapted to draw said half-nut withinsaid slot selectively into and out of engagement with said thread. 5.The rotary finishing machine of claim 2 wherein said motor is in theform of a selectively reversible electric motor supported by saidspindle housing for movement therewith.
 6. The rotary finishing machineof claim 2 wherein said spindle means further comprises means forreleasably holding said spindle housing in a selected position withrespect to said support means.
 7. The rotary finishing machine of claim6 wherein said means for releasably holding said spindle housing in aselected position with respect to said support means comprises areleasable clamp adapted to draw together portions of said support meansagainst said spindle housing on opposite sides of an axial slot in saidsupport means.
 8. The rotary finishing machine of claim 1 wherein saidspindle means further comprises a collet chuck operatively associatedwith said spindle body and adapted to releasably chuck workpieces tosaid spindle body adjacent the lower end of said spindle body.
 9. Therotary finishing machine of claim 1 wherein said spindle arm has alongitudinal axis and said support means is connected to said spindlearm by structure comprising adjusting means for selectively adjustingthe orientation of said spindle body with respect to the longitudinalaxis of said spindle arm.
 10. The rotary finishing machine of claim 9wherein said adjusting means comprises means for selectively adjustingthe orientation of said spindle body in a plane which generallycomprises the longitudinal axis of said spindle arm.
 11. The rotaryfinishing machine of claim 9 wherein said adjusting means comprisesmeans for selectively adjusting the orientation of said spindle body ina plane which is substantially perpendicular to the longitudinal axis ofsaid spindle arm.
 12. The rotary finishing machine of claim 9 whereinsaid adjusting means comprises means for selectively adjusting theorientation of said spindle housing in a plane which generally comprisesthe longitudinal axis of said spindle arm and means for selectivelyadjusting the orientation of said spindle housing in a plane which issubstantially perpendicular to the longitudinal axis of said spindlearm.
 13. The rotary finishing machine of claim 1 wherein said spindlearm comprises outer and inner mutually telescoping members, one of saidmutually telescoping members being supported by said base, the other ofsaid mutually telescoping members being connected to said support means.14. The rotary finishing machine of claim 13 further comprising meansfor selectively adjusting the axiaL position of said other of saidmutually telescoping members with respect to said one of said mutuallytelescoping members.
 15. The rotary finishing machine of claim 14wherein said inner mutually telescoping member is elongated andgenerally tubular and has an axial slot formed therein, and wherein saidmeans for selectively adjusting the axial position of said other of saidmutually telescoping members with respect to said one of said mutuallytelescoping members comprises an elongated externally threaded screwmember journaled within said generally tubular member in parallelrelation to said axial slot, a screw follower slidable within said innermutually telescoping member and threadably engaged with said screwmember, and means supported by said outer mutually telescoping memberand extended through said axial slot is sliding relation to said innermutually telescoping member for holding said screw follower in fixedrelation to said outer mutually telescoping member upon rotation of saidscrew member with respect to said inner mutually telescoping member. 16.The rotary finishing machine of claim 13 wherein said outer mutuallytelescoping member is supported by said base and said inner mutuallytelescoping member is connected to said support means.
 17. The rotaryfinishing machine of claim 16 further comprising means for selectivelyadjusting the axial position of said inner mutually telescoping memberwith respect to said outer mutually telescoping member.
 18. The rotaryfinishing machine of claim 17 wherein said inner mutually telescopingmember is elongated and generally tubular and has an axial slot formedtherein, and wherein said means for selectively adjusting the axialposition of said inner mutually telescoping member with respect to saidouter mutually telescoping member comprises an elongated externallythreaded screw member journaled within said inner mutually telescopingmember in parallel relation to said axial slot, a screw followerslidable within said inner mutually telescoping member and threadablyengaged with said screw member, and means supported by said outermutually telescoping section and extended through said axial slot insliding relation to said inner mutually telescoping member for holdingsaid screw follower in fixed relation to said outer mutually telescopingmember upon rotation of said screw member with respect to said innermutually telescoping member.
 19. The rotary finishing machine of claim 1in which said spindle arm is pivotally mounted to said base for pivotalmovement between an operative position wherein said spindle arm isextended radially inwardly with respect to said bowl and an inoperativeposition wherein said spindle arm is pivoted upwardly from saidoperative position.
 20. The rotary finishing machine of claim 19 whereinsaid spindle arm has an axis and is pivotally mounted to said base forpivotal movement about an axis of pivotal movement oblique to a verticalplane which comprises the axis of said spindle arm.
 21. The rotaryfinishing machine of claim 20 wherein the axis of pivotal movement ofsaid spindle arm is generally horizontal.
 22. The rotary finishingmachine of claim 19 wherein said base provides an integral rest for saidspindle arm in said operative position and said spindle arm is stable insaid operative position.
 23. The rotary finishing machine of claim 19wherein said spindle means further comprises moving means forselectively moving said spindle arm between said operative position andsaid inoperative position.
 24. The rotary finishing machine of claim 23wherein said moving means comprises fluid-driven cylinder mechanismarranged to move said spindle arm from said operative position.
 25. Therotary finishing machine of claim 24 wherein said fluid-driven cylindermechanism comprises a cylinder case pivotally connected to said base andan extensible-retractable rod pivotally connected to said spindle arm.26. The rotary finishing machine of claim 25 wherein saidextensiblE-retractable rod is pivotally connected to said spindle armthrough a crank arm integrally mounted to said spindle arm.